Double-disc flat-lapping or honing machine including a free-wheeling drive connection

ABSTRACT

A dual-disc honing or lapping machine comprising grinding discs journaled for rotation in parallel relation on co-axial shafts; an independent drive for a work-piece mounted on a shaft extending through the tubular shaft of one of the disc shafts; the shaft of the first disc being driven by an electric motor which is rotatable and reversible; the shaft of the second disc being driven by an electric motor through a free-wheeling clutch device which can be optionally engaged whereby all conditions of lapping or honing can be achieved and in which the r.p.m. of the independent electric motors can be controlled.

United States Patent Bovensiepen 1 1 June 17, 1975 [54] DOUBLE-DISC FLAT-LAPPING OR HONING 2,709,876 6/1955 lndge 51/118 MACHINE INCLUDING A FREE-WHEELING g ovenslepen I, DRIVE CONNECTION 3,662,498 5/1972 Caspers 51/1 18 Hans-Friedrich Bovensiepen, Metzkausen, Germany Peter Wolters, Mettmann, Rhineland, Germany Filed: June 11, 1973 Appl. No.: 368,577

Inventor:

Assignee:

Foreign Application Priority Data June 15, 1972 Germany 2229196 References Cited UNITED STATES PATENTS 10/1951 Bonham 192/41 R Primary Examiner-Al Lawrence Smith Assistant Examiner-Nicholas P. Godici Attorney, Agent, or Firm-Holman & Stern [57] ABSTRACT A dual-disc honing or lapping machine comprising grinding discs journaled for rotation in parallel relation on co-axial shafts; an independent drive for a work-piece mounted on a shaft extending through the tubular shaft of one of the disc shafts; the shaft of the first disc being driven by an electric motor which is rotatable and reversible; the shaft of the second disc being driven by an electric motor through a freewheeling clutch device which can be optionally engaged whereby all conditions of lapping or honing can be achieved and in which the rpm. of the indepen dent electric motors can be controlled.

3 Claims, 1 Drawing Figure DOUBLE-DISC FLAT-LAPPING OR HONING MACHINE INCLUDING A FREE-WHEELING DRIVE CONNECTION FIELD OF THE INVENTION The instant invention concerns a double-disc. flatlapping or honing machine comprising two interdepcndent drives for the lapping-or honing-discs. in which at least one of the two drives is switchable to a trailing. synchronizedor counter-rotation of the lappingor honing-disc which is driven by said drive.

BACKGROUND OF THE INVENTION In dual-disc lapping or honing-machines, the workpieces are carried between two operating discs and are thereby worked or honed in opposed parallel planes, e.g.. at their outer periphery. In order to guarantee optimum conditions for various dimensional workpieces, the working discs may be driven by their drives at varying rotational speeds, and at least one working disc can be switched to counter-rotation. synchroneous rota tion. or trailing-rotation or is locked relative to the other working disc. These operational conditions may be obtained with single-motor as well as with dualmotor machines. In single motor machines, a poleswitchable motor is utilized and a switchable reversing gear with a coupling for delayed-action run and locking is used for the machine. The number of variations of settings under various operational conditions. however. is relatively small in single-motor machines, even though an expensive gear arrangement is provided.

Dual-motor machines. however, offer a greater number of variations for settings for various operating conditions.

In a prior art dual-motor machine. the motors are independently switchable in their direction of rotation and and in their speed of rotation. In order to switch to locking and delayed action ofa working disc. no energy is provided to the working motor. The locking is accomplished primarily by bolting the working disc, which sits on the lapping spindle. to the machine body. Such locking is undesirable since the operator of such a machine must consider. in order to avoid demaging the machine before turning on the motor, that the bolt must be released. During a delayed run, the working disc, in addition. must also rotate the gear and the anchor of the motor if there is no special coupling in stalled; accordingly. its number of rotations is thereby reduced. There are hardly any significant variations in the number of rotations between the delayed run and the locking.

It is also known in prior art in dual-disc, flat-lapping or honing machines to install slip couplings into the gear trains which activate the lapping-discs.

SUMMARY OF THE INVENTION It is an object of the instant invention to provide a double-disc flat-lapping or honing machine activated by a dual-motor means. which is switchable to a delayed run or locking in a simpler way than it is possible in prior art machines.

This novel solution to the problem in a dual-disc. flatlapping or honing machine of the above-described types is that one of two gears is provided with a brakemotor which activates the inherent lapping or honing disc by means of a slip-coupling, and the other of the two gears represents the gear which can be switched to synchronism (same speed and direction of rotation) counter-rotation.

In the improved dual-disc lapping or honing machine of the instant invention. it is possible when the brakemotor is switched off. i.e., in a stopped condition. to switch the working disc to delayed run or to lock same by means of the rotational direction of the workpiece holder. During the locking. the free-wheeling coupling. due to one direction of rotation, effects a nonotatable connection between the stopped brakc-motor and the working disc. while during delayed run. the frcewheeling. due to the other direction of rotation. releases the non-rotatable connection between the stopped brake-motor and the working-disc. Since the working disc during the delayed (or trailing) run contrary to prior art machines operates along with the gear and the motor, it runs with little resistance. so there results almost no relative movement between workpiece and work-disc. Also. no special mechanical bolting means are required, but in one rotational direction of the working disc. the locking is accomplished by means of the brake-motor itself. and no danger exists as is the case in prior art machines i.e.. the machine will be damaged by the locking operation. In order to further influence the operational conditions of the lapping disc. the number of rotations of the gears may be adjustable.

According to one embodiment of the instant invention, a free-wheeling operation is provided with switchable brake means. This embodiment offers the possibility of freely selecting the rotational direction of the activating discs in free-wheeling operations as well as in braking operations.

The inventive concept may be incorporated in lapping or honing machines with more than two discs.

Further objects and advantages will become apparent from the following description of an exemplary embodiment when taken with the drawing forming a part thereof in which:

BRIEF DESCRIPTION OF THE DRAWING The single FIGURE of the drawing. shows in elevation. diagramatically. a dual-disc lapping or honing ma chine incorporating the principles of the invention.

DESCRIPTION OF A PREFERRED EMBODIMENT A lower grinding disc I is rotatably journaled in a suitable housing (not shown) of the dual'disc lapping or honing machine. An electrically-operated motor 2 is provided to activate the working disc I; the motor 2 is drivingly connected to a hollow spindle 6, integral with the working disc 1, by means ofa belt drive 3 entrained over a drive disc 4, connected to a worm gear 5 engaging a meshing gear fixed to the spindle 6. The motor 2 is adjustable as to its r.p.m. by means of a conventional pole-switching and/or pole-reversal switching, and its direction or rotation is reversible; the motor 2 may also function as a braking motor.

A spindle 7, connected to a workpiece holder 8, is joumaled in the hollow spindle 6 and the spindle 7 is independently rotated by a motor 10 through suitable drive gear means 9.

A second working disc 11 is connected to a gear spindie or shaft 12 positioned in the housing of the machine and extends coaxially to and above the working disc 1. The actuating means 13 for the upper working disc II serves as a braking-motor through a speed-reduction gear 14 and a belt drive l5, l6, 17. The rotational speed of the brake motor 13 is adjusted by means of suitable pole-switching. The belt pulley 15 arranged at the output end on the gear or transmission 14 is constructed to function as free-wheeling clutch, and the belt pulley 17 is circumposed about and fixed to the spindle 12.

When honing parallel or opposed faces of flat workpieces, the grinding discs 1, 11 are driven with nearly the same r.p.m. but in the opposite directions. if both workpiece surfaces have the identical grind characteristics and the same amount of mterial is to be removed from both opposed surfaces of the workpiece. Should the amount of material vary with respect to the opposed sides of the workpiece; this often being necessary for workpieces with variable sizes of parallel surfaces, then the r.p.m. of the upper working disc 11 is either reduced, through control of the braking-motor 13, or the upper working disc 11 is locked by switching off the brake-motor, or, due to its frictional engagement with the workpieces, it is carried along as is permitted by the free-wheeling clutch or coupling means 14. The freewheeling means 14 may be optionally switchable during the locking operation of braking-motor 13. Such a free-wheeling means provides the additional advantage of selective switching in one direction of rotation as well as in the opposite rotational direction of locking and free-running. if there is a simple free-wheeling means as proposed, it then depends on the direction of rotation of the workpiece holder 8 if the upper working disc 11 is to be carried along or if it is being locked.

Large workpieces, which are to be honed between the parallel discs, are ground in identical directions of rotation and at substantially the same r.p.m. of the grinding discs 1, ll.

workpieces which are formed circular at their outer periphery, are ground under varying relative rotational movements of the two working discs 1, ll.

1 claim:

1. In a dual-disced flat-lapping and honing machine, comprising in combination:

a pair of confronting rotatable. working discs, a tubular drive shaft integral with and projecting axially from the axis of rotation, of one disc;

electrical drive means operatively connected to said tubular drive shaft, said electrical drive means having an adjustable r.p.m. and being reversible in its direction of rotation and functioning as a braking motor:

a second shaft projecting axially through said tubular drive shaft;

a motor operatively connected to said second shaft for independently rotating the same within said tubular drive shaft:

a workpiece holder connected to said second shaft and disposed in the working plane of the one working disc;

a third drive shaft projecting axially from said other working disc for rotatting the same; and

an adjustable, reversible braking motor operatively connected to said third shaft through a freewheeling clutch means in such a way that when said adjustable braking motor is turned off, frictional engagement between said other working disc and the workpiece rotating in a first direction causes free rotation of said other disc and reverse rotation of the workpiece causes said other disc to become locked against rotation.

2. In a dual-disced flat-lapping and honing machine in combination:

a pair of confronting rotatable working discs and a rotatable workpiece holder disposed between two working discs, a reversible motor operatively connected to the first disc for optionally controlling the direction of rotation of the first disc, a motor operatively connected to the workpiece holder, drive means operatively connected through a free wheeling coupling to the second working disc and functioning as a braking motor in such a way that when the braking motor is turned off, frictional engagement between workpieces of the said workpiece holder rotating in a first direction and the second working disc causes the rotation of the second working disc and reverse rotation of the workpieces of the workpiece holder causes the second working disc to become locked against rotation.

3. In a dual-disced flat-lapping and honing machine in combination:

a pair of confronting rotatable working discs and rotatable workpiece holder disposed between the two working discs, a motor operatively connected to the first disc, a motor operatively connected to the workpiece holder, drive means operatively connected through a free-wheeling coupling lockable in opposite directions of rotation to the second working disc and functioning as a braking motor reversible in its direction of rotation in such a way that when the braking motor is turned off, frictional engagement between the workpieces of the said workpiece holder rotating in a first direction and the second working disc causes free rotation of this working disc and reverse rotation of the workpieces of the workpiece holder causes this disc to become locked against rotation respective to the locking direction of rotation of the free-wheeling coupling. 

1. In a dual-disced flat-lapping and honing machine, comprising in combination: a pair of confronting rotatable, working discs, a tubular drive shaft integral with and projecting axially from the axis of rotation, of one disc; electrical drive means operatively connected to said tubular drive shaft, said electrical drive means having an adjustable r.p.m. and being reversible in its direction of rotation and functioning as a braking motor; a second shaft projecting axially through said tubular drive shaft; a motor operatively connected to said second shaft for independently rotating the same within said tubular drive shaft; a workpiece holder connected to said second shaft and disposed in the working plane of the one working disc; a third drive shaft projecting axially from said other working disc for rotatting the same; and an adjustable, reversible braking motor operatively connected to said third shaft through a free-wheeling clutch means in such a way that when said adjustable braking motor is turned off, frictional engagement between said other working disc and the workpiece rotating in a first direction causes free rotation of said other disc and reverse rotation of the workpiece causes said other disc to become locked against rotation.
 2. IN A DUAL-DISCED FLAT-LAPPING AND HONING MACHINE IN COMBINATION: A PAIR OF CONFRONTING ROTATABLE WORKING DISCS AND A ROTATABLE WORKPIECE HOLDER DISPOSED BETWEEN TWO WORKING DISCS, A REVERSIBLE MOTOR OPERATIVELY CONNECTED TO TTHE FIRST DISC FOR OPTIONALLY CONTROLLING THE DIRECTION OF ROTATION OF THE FIRST DISC, A MOTOR OPERATIVELY CONNECTED TO THE WORKPIECE HOLDER, DRIVE MEANS OPERATIVELY CONNECTED THROUGH A FREE-WHEELING COUPLING TO THE SECOND WORKING DISC AND FUNCTIONING AS A BRAKING MOTOR IN SUCH A WAY THAT WHEN THE BRAKING MOTOR IS TURNED OFF, FRICTIONAL ENGAGEMENT BETWEEN WORKPIECES OF THE SAID WORKPIECE HOLDER ROTATING IN A FIRST DIRECTION AND THE SECOND WORKING DISC CAUSE THE ROTATION OF THE SECOND WORKING DISC AND REVERSE ROTATION OF THE WORKPIECES OF THE WORKPIECE HOLDER CAUSE THE SECOND WORKING DISC TO BECOME LOCKED AGAINST ROTATION.
 3. In a dual-disced flat-lapping and honing machine in combination: a pair of confronting rotatable working discs and rotatable workpiece holder disposed between the two working discs, a motor operatively connected to the first disc, a motor operatively connected to the workpiece holder, drive means operatively connected through a free-wheeling coupling lockable in opposite directions of rotation to the second working disc and functioning as a braking motor reversible in its direction of rotation in such a way that when the braking motor is turned off, frictional engagement between the workpieces of the said workpiece holder rotating in a first direction and the second working disc causes free rotation of this working disc and reverse rotation of the workpieces of the workpiece holder causes this disc to become locked against rotation respective to the locking direction of rotation of the free-wheeling coupling. 